The objective of this proposal is to validate the feasibility of a microwave tomographic (MWT) method and system for non-invasive detection of cardiovascular disorders. The major hypothesis of this project is that changes in myocardial physiological and pathological conditions, caused by blood flow reduction, ischemia, infarction and others, can be non-invasively detected by microwave tomography. This hypothesis is based on the results of our preliminary studies, which demonstrate that: 1) myocardial dielectrical properties, which could be imaged with microwave tomography, depend on physiological and pathological conditions of myocardial tissue, 2) using our previously developed microwave tomographic systems and image reconstruction methods we have successfully reconstructed mathematical models, physical phantoms and biological objects and 3) the degree of change in myocardial dielectrical properties caused by various disorders is within the scale of detection capabilities of microwave tomography. In the proposed course of study, the 3D microwave tomographic systems, that we have developed will be upgraded to meet necessary technical requirements for imaging static biological objects and animals. To achieve a quantitative reconstruction of the distribution of dielectrical properties, the image reconstruction algorithms will also be further developed. This will allow for the accomplishment of the specific aims outlined during the three-year grant period which will focus on imaging excised static hearts under normal conditions and with models of acute ischemia and chronic infarction. The final aim of this study is to image normal euthanized animals as ell as those with acute myocardial ischemia and chronic infarction.